Right Ventricular Implantable Cardioverter Defibrillator Lead Implantation Tbrougb a Persistent Left Superior Vena Cava ANDREAS MARKEWITZ and SOREN MATTKE* From the Departments of Cardiac Surgery and *Cardiology, Ludwig-Maximilians-University, Grosshadern Hospital. Munich, Germany MARKEWITZ, A., ET AI,.: Right Ventricular Implantable Cardioverter Defibrillator Lead Implantation Through a Persistent Left Superior Vena Cava. A 60-year-old woman required implantation of an ICD be- cause of a hypotensive ventricular tacbycardia refractory to four different antiarrbythmic drugs. Preoper- ative diagnostics revealed a persistent left SVC as tbe only major venous return from tbe upper part of tbe body to tbe beart. Under local anestbesia, a tripolar lead was advanced tbrougb tbe left SVC into tbe rigbt ventricular apex. Following successful testing, an active can ICD device was implanted, wbicb is func- tioning well during a follow-up period of 9 montbs. (PACE 1996; 19:1395-1397) cardioverter defibrillators, lead implantation, persistent left superior vena cava Introduction A persistent left superior vena cava (SVC) ap- pears to be common in patients who are candi- dates for implantable cardioverter defibrillator (ICD) therapy at least at our institution; 3 out of 200 patients scheduled for ICD implantation showed this anatomical variant. However, prob- lems arise only if the persistent left SVC is the only venous return to the heart from the upper part of the body. We report a patient with this anomaly, in whom successful right ventricular (RV) ICD lead placement was possible. Case Report The 6n-year old woman experienced a syn- cope due to a documented ventricular tachycardia (VT). Cardiac catheterization and myocardial biopsy revealed RV dysplasia with an otherwise normal heart. The inability to introduce a pul- monary artery catheter through the right internal jugular vein into the heart led to further angio- graphic examinations, and the diagnosis of a per- sistent left SVC with an absent right SVC was es- tablished. Address for reprints: Andreas Markewitz. M.D.. OFA. Dept. of Cardiovascular Surgery, Central Military Hospital, Ruebe- nacher Str. 170, D-56072 Koblenz, Germany. Fax; (49) 261-281- 387. Received December 18, 1995; accepted January 24, 1996. Programmed ventricular stimulation could easily induce a hypotensive VT. which was termi- nated by overdrive stimulation. Four antiarrhyth- mic drugs (sotalol. mexiletine amiodarone, and propafenone) were tested, but none could control the VT. Thus, the decision to implant an ICD was made. Under local anesthesia and following cephalic vein cutdown, a tripolar RV lead (Medtronic 6936. Medtronic Inc.. Minneapolis, MN, USA) was introduced in the persistent left SVC using a ] shaped stylet. With a straight stylet, the lead was further advanced through the coro- nary sinus into the right atrium. The stylets again were exchanged, and with a U shaped stylet the lead could be introduced into the right ventricle, positioned nearby the RV apex. Stimulation threshold measured 1.6 V at 0.5 ms with a pacing impedance of 621 fl, R wave amplitude was 7 mV with a slew rate of 0.85 V/s. With the defibrillation cathode in place, the testing device was inserted in a suhpectoral pocket. Ventricular fibrillation (VF) was induced by using a T wave shock, and the device successfully reverted VF into sinus rhythm twice with an energy of 24 J and the device was implanted (Fig. 1). For pocket formation and defibrillation efficacy testing, systemic sedation and analgesia was achieved by intravenous ad- ministration of midazolam and alfentanil. During follow-up of 9 months, a total of 23 episodes of VT were successfully treated by antitachycardia stim- ulation (n = 19) or cardioversion (n = 4), PAGE. Vol. 19 September 1996 1395